Category: ZT Logbook

One of our big projects this year is the conservation of three large fragments of an Assyrian wall paintings discovered by Dirk and his team in the Bronze Palace in 2008 and 2009. The Assyrians typically decorated their palaces with ornate figures and geometric designs. In the Assyrian heartland of modern-day northern Iraq, at places like Nineveh, these decorations were made by carving enormous flat panels of limestone called orthostats which lined the interior walls of the public buildings.

Here is an orthostat now found at the British Museum showing the Assyrian king hunting. These are some of the most stunning and iconic images we have from ancient Assyria.

Out on the northern frontier, at places like ancient Tushhan, palaces were not so elaborately adorned and wall paintings or frescoes were used in the place of carved stone orthostats. The paintings were made on white plaster with black, red, and blue paint. Because they are made from perishible substances, almost all of the wall paintings at Tushhan and other Assyrian imperial centers have been lost over the past 2700 years.

In 2008 and 2009, we found several large fragments that were preserved when the walls of the palace collapsed in upon themselves and sealed the plaster beneath the rubble of the mudbrick walls. These photographs from 2009 show Dirk carefully cleaning the surface of one of the paintings, and below that two of our conservation team, Charlotte Rerolle and Yvonne Helmholz, using a chemical consolidant to hold the plaster together so it could be lifted in one piece.

Because they were so delicate, we decided to lift the large fragments intact with the goal of conserving them in the laboratories of the Diyarbakir Museum in a later season. This was done by first digging the soil out from around the fresco to raise it above the surrounding ground level, a technique called pedestalling. Next we wrapped the edges of the fresco fragment in a non-adhesive covering akin to kitchen plastic wrap. Then we covered the entire perimeter in gauze bandages soaked in plaster to create a hard plaster shell around the fresco to give it stability.

Finally, an iron sheet was driven beneath the fresco, slicing through the soil pedestal, freeing the large fragment, which allowed us to remove the entire piece intact. Additional supporting material was added to the fragment before it was loaded on a truck and moved first to our depot, and then on to the Museum storeroom. By the time we were done, each of these “eggs”, as we nicknamed them, weighed enough to require a number of Turkish workmen to lift on poles.

Fast forward to 2014. The “eggs” have been sitting in a storage room in the Diyarbakir Museum for years awaiting our attention and finally this year we have a team of three conservators – Yvonne who was here in 2009, Lourdes Mesa Garcia, and Olga Emgrund – whose job is the crack open the eggs, clean them, and prepare them for exhibition. Here is what one of the plaster frescoes looked like at the beginning of the 2014 season. Yvonne has cracked open the first egg and is gently brushing away the dirt. The process of conservation will take weeks, or even months, before the wall fresco is stable enough to be put on display.

We will keep you up on progress on this conservation project. Wait and see!

One of the more exciting elements of this year’s work is our collaboration with the regional Diyarbakır Archaeology Museum. There has been an archaeological museum in Diyarbakır since 1934 and the current building has been in use since 1985. The 1980’s building is now sadly in need of repairs and plans for opening a new cultural center, including a museum, in the old citadel (Iç kale) in Diyarbakır have been in the works for years and are nearing completion, so soon there will be a new home for all of the Ziyaret Tepe artifacts.

The new museum is in a spectacular old stone building on a high cliff overlooking the Tigris River at the edge of the city. The building has been restored as part of a complete refurbishment of the Iç kale. I’ll tell you more about that later.

Over the winter, Aytaç Coşkun, a craftsman working for the museum undertook a project to reconstruct a small portion of one of the large mosaic courtyards from the Assyrian public buildings excavated in the lower town. Here are some photographs of Courtyard 20 during excavation, a plan showing the location of three courtyards (2, 11, 20 on the plan), and a detailed photograph I sent to Mr. Coşkun, amongst other documentation.

The original mosaics were made with stones selected from the Tigris River and for his reconstruction, Mr. Coşkun also hand-selected hundreds of river stones of various sizes sorted into black and white groups to imitate the original materials. These stones were placed in a cement mortar (the Assyrians used a mud mortar) in the entrance to one of the two galleries dedicated to Ziyaret Tepe in the new museum. You can see his team at work below.

Mr. Coşkun used a movable frame for constructing each square of the mosaic. He started by lining the edges with flat cobbles laid on edge, as seen in the original Assyrian design. Next, he selected appropriately sized and shaped colored stones to fill in the interior spaces, moving on to the next part of the frame when the mortar had set. Unlike the cut stone tesserae that were used by later Roman craftsmen, Assyrian mosaics employed natural stone shapes.

The result is quite impressive and will give museum visitors a real sense of what the mosaics would have looked like in ancient times. The Assyrian originals were over 10m (30 feet) on a side, so this is just a sampling. (The wire sticking out is for lighting a small pedestal that will sit on the center of the mosaic.) Well done, Mr. Coşkun!

This blog is written for my Materials Science students back at UAkron, who are busy learning some chemistry essentials with my co-instructor, Prof. Richard Elliott of our Department of Chemical and Biomolecular Engineering. A few days ago, we hosted two visiting scholars for a two day visit to Ziyaret Tepe: Prof. Thomas Zimmerman, the head of the archaeology department at Bilkent University and Dr. Latif Özen, a chemist and conservator in the Laboratory for Restoration and Conservation at the Museum of Anatolian Civilisations, both in Ankara. Thomas and Latif brought a portable x-ray fluorescence unit (p-XRF) to study the elemental composition of some of our artifacts.

In particular, we were interested in the metal artifacts found in the cremation burials in the Bronze Palace, which we assumed were made of copper alloys, most likely bronze (an alloy of bronze and tin). An artifact is placed on the sensor of the p-XRF and is subjected to a high energy x-ray beam. The sensor monitors the emission of energy by excited atoms on the surface of the artifact (to a depth of 3 microns); the specific characteristics of the energy emitted tells us what atoms are present.

In initial tests, we found that some of our ancient metal artifacts (not from the cremation burials) were nearly pure copper, while others were copper-tin bronze, and at least one was made of an alloy of copper and arsenic (called “arsenical bronze”). We also found that one team member’s “white gold” ring was nickel plated and that my 18K gold wedding band is actually 14K gold since the p-XRF provides a weight percent so we not only what elements are present, but their relative percentages.

Here’s the question for the Materials Science class. All of the artifacts tested initially by Thomas and Latif from the burials had very, very low concentrations of the element vanadium (V, atomic number 23). In their previous analyses of 1500+ artifacts from ancient Anatolia, they did not have evidence for the presence of vanadium in any artifacts and yet it was consistently present in all the artifacts from the cremation burial at Ziyaret Tepe that they initially tested. This was an unanticipated surprise. We subsequently tested earth samples of the burnt lining of two of the cremations and they too had a very, very low vanadium concentration, a few parts per million. In other words, this element is present in the edges of the cremation pits, not just in the metal artifacts.

So, UAkron students, what are some possible explanations for the presence of vanadium in these archaeological contexts and artifacts? What can you tell me about vanadium’s properties, occurence in nature, and the various states in which it occurs? The concentrations are a fraction of a percent, so it is a trace element in these artifacts.

Disclaimer: these results are only very preliminary and need statistical analysis to verify and to provide us with more precise estimates of the concentration. Likewise, Thomas and Latif continued their analyses after leaving the dig house, working in the museum until their flight home to Ankara, so there are some analyses for which I have no information about at all. It’s an interesting little chemistry puzzle for the beginning of the semester. I’ll pass along any other details as they emerge.

As you all know, Ziyaret Tepe is pretty well off the beaten path and it is a rare treat to have visitors to the site. As such, it was a real honor – or should we say, honour – for the team to greet the British Ambassador to Turkey, His Excellency Sir David Reddaway, who came a few days ago for a short stay to meet our team and tour Ziyaret Tepe and some other local places of historical interest. The reason for Sir David’s visit was not entirely archaeological, however. His son, Milo, has been working with us for the past three weeks and Sir David came to see Milo in action.

Milo is just entering the final year at King’s School Canterbury, an institution which was founded in 597 – contemporary with our own late Roman layers! He has a keen interest in archaeology and, we are delighted to say, this now includes the Assyrians. In addition to a great exposure to how archaeologists work in the field, the experience has also allowed Milo to complete the final requirement for his gold level Duke of Edinburgh Award.

Milo has worked most closely with John, but we also made sure that he got experience doing geophysical survey, working in the laboratories, in the sherdyard, and observing the specialists. Many archaeological field methods, as I often tell my undergraduate students back at the University of Akron, can only be learned hands-on at the excavation. Here Milo is getting some practice digging mudbrick, which involves experiencing the feel of the material and learning how the soil breaks apart from intact mudbrick under a small pick. The only place to become an expert excavator is in the bottom of a trench.

In a pit cutting into the earliest level of the Bronze Palace, Dirk and his team made an unexpected discovery – a complete, unbaked clay tablet with cuneifom writing. Here’s a photo of what it looked like when it came out of the ground. Not much to look at! There were two small fragments that were broken off during excavation; the tablet was damp and very fragile.

Under the expert attention of our project conservator, Lourdes Mesa Garcia (a private conservator from Madrid), the fragments were joined to the tablet and the entire artifact was cleaned using a needle, a tiny soft paint brush, and a very gentle air blower. We let the tablet dry for four days (yes, I’ve been holding out on you) before cleaning it to clarify the signs.

Look at the difference!

John has made a preliminary assessment and determined that the tablet is an accounting list of 25 textiles of several different types. There is a date on the tablet, but only giving the day and month. Sadly, no year is recorded. There are also two Assyrian personal names.

What is particularly important about this tablet is that it appears to be Middle Assyrian in date, meaning that it was written between (very roughly) 1300 – 1050 BC, several centuries before all the other tablets we have found. Assyriologists like John can date tablets according to their paleography (broadly, the study of ancient languages, including their written form)

In ancient Assyrian, just like other languages, the vocabulary, grammar, and shapes of the letters (here cuneiform wedges) change over time. Think of the differences in language and writing between Beowulf, Chaucer’s Canterbury Tales, and a modern novel – all written in English. Over time, the written form of cuneiform changed and two of the cuneiform signs used in our tablet were used during the Middle Assyrian period, but are not found in Late Assyrian texts; their archaic form suggests the earlier date. This is the earliest written material we have from Ziyaret Tepe. We also know that the palaces in Assyrian cities were often involved in textile production and although we can’t say that this tablet proves this was the case at Assyrian Tushhan, it is one possible explanation for why such a tablet would have been stored in the palace archives.

One of our on-going projects this year has been the recovery and analysis of paleobotanical samples: charred seeds, wood charcoal, and other plant remains recovered via flotation. When we reach a floor deposit, or a hearth with ashy remains, or a storage pit, we take a sample of the soil and separate out the earth from the organic remains by floating the samples in water. The earth dissolves, rocks, pottery and small artifacts sink, and what is left floating are charred seeds.

After the samples are dried, our specialists – Melissa Rosenzwieg and Lucas Proctor – examine the ancient plant remains present in the soil under a microscope and identify them by comparing them to a reference collection taken from known species. This is a time-consuming and tedious task, and Melissa and Lucas have been working hard all season to classify the plants used for food, animal fodder, fuel, and even the weeds that tell us about the diet, economy and environment of Ziyaret Tepe’s ancient inhabitants.

Melissa, a PhD student from Chicago, has been here previously and is primarily concerned with our Assyrian levels. Lucas is one of our new faces. He is a new PhD student at the University of Connecticut and was working in northern Iraq before coming to Turkey. Here they are consulting over a sample in our field laboratory.

Lucas’ task at Ziyaret Tepe was to analyze the paleobotanical remains from the Roman period buildings excavated in earlier seasons. He just finished the identification of the last sample this morning and now will undertake a statistical analysis of the counts before writing his final report. Overall, the Roman samples generated an array of botanic species that have not been found in the Assyrian samples, suggesting that the flora surrounding Ziyaret Tepe was in some ways quite different 1,000 years after the Assyrians left Tushan.  Lucas also told me that we have evidence for the Romans growing grapes and utilizing poppies.

There was also a single grain of rye from his samples, the first we’ve seen of rye at Ziyaret Tepe. What to make of a single piece of rye? Well, we have to wait for the analysis before drawing any conclusions, but our picture of Roman life here has already improved.

We’ll, we’re two weeks into the digging and making good progress in four excavation areas.

On the citadel mound, Dirk Wicke has been continuing to excavate the earliest levels of the Bronze Palace. As you might recall from earlier posts, the Bronze Palace is a monumental mudbrick building on the eastern edge of the citadel. We had previously established that the building had three major building phases during the nearly three centuries in which it was in use (c. 882 BC to 611 BC). Because it is deeply buried under later rennovations, the earliest phase of the palace has been the least explored. This season, Dirk has removed a section of the second phase building over an area of about 10m by 10m (30 feet by 30 feet) and has exposed more of the earliest building level, which we believe to be 9th century BC in date. In a few places, Dirk and his team have reached the very bottom of the Late Assyrian palace and, below the foundations, have found a cobbled floor and parts of two walls that belong to an even earlier large building dating to the Middle Assyrian period (very roughly 1300-1050 BC here). We know that around 882 BC, the late Assyrian king Ashurnasirpal II claimed to have completely rennovated an abandoned palace built by an earlier ruler at Tushhan. We hoping for more evidence to help us securely date these earliest levels below the Bronze Palace.

In the lower town, we have three operations running simultaneously. Mary Shepperson, a recent PhD from University College London, has returned to the project after several years away. It is great to have Mary back on site (and congrats, Dr. Shepperson!). Her excavation area is Operation Y located in the southwestern corner of the lower town. This is probably our most ambitious trench given it’s size (10m by 20m) and that we have less than five weeks of actual digging time. In Operation Y, our past geophysical surveys suggested that the city wall makes a sharp jog here and for years I have thought that there was a large building with rooms arranged around four open courtyards tucked into the jog in the city wall. Mary is now looking for physical proof of that building. She has found the city wall as well as a few later graves – you can see her excavating one above. Mary is close to the depth where we expect to find the tops of the walls of my hypothetical building. Fingers crossed.

John MacGinnis is overseeing the excavations in Operation W where he is looking at the earliest levels of a large mudbrick building that was excavated in the lower town from 2001-2010. Like with Dirk’s project, John is hoping to find traces not only of the earliest Late Assyrian building phases, but to see if there were even earlier building levels. You can see his excavation area below.

Finally, Kemalettin is making great progess on the private housing located adjacent to the city gate in Operation K, as I reported earlier. He extended his trench to the east and now has three clearly defined rooms. I’ll get you more details soon.

About 90km north of Diyarbakir there is a place in the Taurus Mountains where the Dibni Su, one of the two main sources of the Tigris River, comes flowing out of a large cave. The Dibni Su actually originates much deeper in the mountains, but the ancient Assyrians thought this to be the source of the Tigris and it is a dramatic landscape that had great significance to them. The modern name of the place is Birkleyn Gorge.

 We know that the Assyrians marked this spot as significant since there still exist four small rock inscriptions made by the Assyrian kings Tiglath-pileser I (1114-1076 BC) and Shalmaneser III (858-824 BC): three in the lower cave from which the Dibni flows, and one in an upper cave a few hundred feet so higher up in the mountains. We have textual and other representational art that tells us that the kings presided over commemorative events that happened here three thousand years ago. This was an area far from the Assyrian frontier and one has to imagine that this was an arduous journey for the Assyrian king and his court to make, deep into territory outside of their military control.

If you look at the above photograph you will see two black spray-painted graffiti on the far left (a modern form of rock inscriptions, I guess). The Dibni Su flows out of the cave in this photograph and in places within the cave is well over one’s head in depth. The photograph below shows the area with the two black graffiti in greater detail and you can see that just above the spray paint, and a bit to the right of a circular broken area on the rock face, is a figure of the Assyrian king Tiglath-pileser I. To the king’s left is a cuneiform inscription, barely legible on the uneven surface. He is seen in profile, with a flat topped hat and flowing robes.

During our bayram holidays, we made the long drive from Bismil north across the last vestiges of the northern Tigris River valley and into the mountains to see the inscriptions. It was quite an adventure. The lower cave (seen in the photographs above) requires a bit of shallow wading and navigating some steep slopes to find. The upper cave in the Birkleyn Gorge can only be accessed by a trail crossing a narrow rocky ledge at one point and requiring a scramble over boulders with uneven footing well-worn by visitors. The inscription at the upper cave sits at the entrance. Here Willis is pointing to part of a cuneiform inscription (it is the word “Assur”) and you can see the cuneiform wedges quite clearly (again beneath a modern graffiti). The figures of the king in all four inscriptions are small, maybe three feet tall.

It was quite an interesting trip and a nice break from work at the dighouse. The next day I heard a bit of (cheerful) grumbling about aching legs from the climb and a few calls to revisit the cool caves and icy waters of the Dibni Su as we returned to hot and dusty Bismil and to work on site at the end of bayram.

It was certainly a busy week for us and there is plenty to report from the field. The end of Ramadan in Turkey is marked by a long bayram holiday that just started, so after a shortened working day yesterday, our local workers, government representative, and house staff left for their homes and families to celebrate. We will be working at the dighouse during the holiday which ends on Saturday. This is a perfect time to catch up on my blog entries and tell you about some of the interesting finds we’ve made.

One of our most important goals for this season is the excavation of Assyrian private houses in the lower town. Archaeologists are just as interested in the lives of everyday people as we are about the “great events” of history, palaces and kings and this season we are reopening excavations in Operation K, an area we first excavated nearly a decade ago, where Kemalettin found the remains of a modest house built adjacent to the interior of the southern city wall. One focus of this new study is an intensive study of the ancient plant and animal remains preserved within the house which tell us about the diet, economy, and environment in which the Assyrians lived.

Kemalettin started work in a 5m by 10m area (roughly 15 feet by 30 feet), in a trench immediately adjacent to the original Operation K excavations. His trench is located in a field that was recently plowed, so the top 25 or 30cm (10-12 inches) of the soil were completely jumbled up and our workers quickly removed this layer. Immediately below, Kemalettin and his team found an area of paved cobbles with part of a ceramic drain in the northern part of the trench. The whole area was badly disturbed by modern plowing, so it is difficult to say much about this pavement other than it was perhaps a courtyard or a street and, given what we have learned elsewhere on the site, may be of Late Roman date. We found part of a Roman period roof tile, but very little in the way of clearly Roman period materials.

More importantly, Kemalettin was also able to find the tops of the mudbrick walls that form the extension of the plan of the Assyrian house we excavated earlier. This is very exciting since it means that we will have plenty of time to explore the house even with a shortened digging season.

We found a grave to the south of the OpK house, outside of the house itself but adjacent to the wall, which appears to be Assyrian in date. One of the questions that we hope to answer this year is where the non-elite Assyrians at Tushhan buried their dead. There is no external graveyard for the site (although some of you will remember Operation S where we explored an area south of Ziyaret Tepe where local farmers said they found a possible burial site or graveyard, but where we were unable to locate any cultural remains). At the end of this week, Kemalletin found two additional burials, both inside of the house and immediately below the floor so we now know that at least some of the dead at ancient Tushhan were buried inside their houses. I’ll share some details in later blog post.